XAllocClassHint(3X11) XLIB FUNCTIONS XAllocClassHint(3X11)NAME
XAllocClassHint, XSetClassHint, XGetClassHint, XClassHint
- allocate class hints structure and set or read a win-
dow's WM_CLASS property
SYNTAX
XClassHint *XAllocClassHint()
XSetClassHint(display, w, class_hints)
Display *display;
Window w;
XClassHint *class_hints;
Status XGetClassHint(display, w, class_hints_return)
Display *display;
Window w;
XClassHint *class_hints_return;
ARGUMENTS
display Specifies the connection to the X server.
class_hints
Specifies the XClassHint structure that is to be
used.
class_hints_return
Returns the XClassHint structure.
w Specifies the window.
DESCRIPTION
The XAllocClassHint function allocates and returns a
pointer to a XClassHint structure. Note that the pointer
fields in the XClassHint structure are initially set to
NULL. If insufficient memory is available, XAlloc-
ClassHint returns NULL. To free the memory allocated to
this structure, use XFree.
The XSetClassHint function sets the class hint for the
specified window. If the strings are not in the Host
Portable Character Encoding, the result is implementation-
dependent.
XSetClassHint can generate BadAlloc and BadWindow errors.
The XGetClassHint function returns the class hint of the
specified window to the members of the supplied structure.
If the data returned by the server is in the Latin
Portable Character Encoding, then the returned strings are
in the Host Portable Character Encoding. Otherwise, the
result is implementation-dependent. It returns a nonzero
status on success; otherwise, it returns a zero status.
To free res_name and res_class when finished with the
strings, use XFree on each individually.
X Version 11 Release 6.4 1
XAllocClassHint(3X11) XLIB FUNCTIONS XAllocClassHint(3X11)XGetClassHint can generate a BadWindow error.
PROPERTIES
WM_CLASS Set by application programs to allow window and
session managers to obtain the application's
resources from the resource database.
STRUCTURES
The XClassHint structure contains:
typedef struct {
char *res_name;
char *res_class;
} XClassHint;
The res_name member contains the application name, and the
res_class member contains the application class. Note
that the name set in this property may differ from the
name set as WM_NAME. That is, WM_NAME specifies what
should be displayed in the title bar and, therefore, can
contain temporal information (for example, the name of a
file currently in an editor's buffer). On the other hand,
the name specified as part of WM_CLASS is the formal name
of the application that should be used when retrieving the
application's resources from the resource database.
DIAGNOSTICS
BadAlloc The server failed to allocate the requested
resource or server memory.
BadWindow A value for a Window argument does not name a
defined Window.
SEE ALSOXAllocIconSize(3X11), XAllocSizeHints(3X11), XAl-
locWMHints(3X11), XFree(3X11), XSetCommand(3X11), XSet-
TransientForHint(3X11), XSetTextProperty(3X11), XSetWM-
ClientMachine(3X11), XSetWMColormapWindows(3X11), XSetWMI-
conName(3X11), XSetWMName(3X11), XSetWMProperties(3X11),
XSetWMProtocols(3X11), XStringListToTextProperty(3X11)
Xlib - C Language X Interface
X Version 11 Release 6.4 2
